A motor vehicle comprises a drive train having an internal combustion engine. The internal combustion engine is equipped with a turbocharger which comprises an exhaust gas turbine and a compressor. The exhaust gas turbine is driven from a current of exhaust gas from the internal combustion engine and itself drives the compressor which compresses fresh air for the internal combustion engine. The pressure of the fresh air which is produced in the process is referred to as charging pressure. The charging pressure can be controlled, for example, by correspondingly adjusting a variable turbine geometry of the turbocharger. Other possible ways of adapting the charging pressure comprise discharging excess compressed air on the compressor side or directing part of the exhaust gas stream past the exhaust gas turbine.
In particular, when the drive train is used in a motor vehicle, rapid or frequent load changes of the internal combustion engine may be necessary. In this context, different parameters of the internal combustion engine, one of which is the charging pressure, are changed. The most decisive factor for a harmonious buildup of tractive force is that the actual charging pressure of the turbocharger follows a predefined setpoint charging pressure as rapidly as possible and as far as possible without overshooting. For this purpose, until now to a certain extent costly proportional-integral-differential controllers (PID controllers) have been used, the parameters of which were costly to change.
DE 10 2011 006 227 A1 relates to technology for performing pilot-control of a controller. In this context, the target variable is changed suddenly in successive phases.
DE 197 51 977 A1 proposes adjusting a turbine geometry on a turbocharger as a function of the sum of a predefined value and of a pilot-control value.
DE 10 2007 050 026 A1 relates to the determination of a fault during the adjustment of a value by closed-loop control to a predetermined value.